Processes that would be available for producing glycidyl carboxylates include (a) a process in which they are produced by a desalting condensation reaction of a carboxylic acid or a salt thereof with epichlorohydrin, and (b) a process in which the allyl group of an allyl ester is epoxidized. As for glycidyl 2-hydroxyisobutyrate having the structure represented by the formula (2), an example of the process (a) is known, in which glycidyl 2-hydroxyisobutyrate is produced from 2-hydroxyisobutyric acid and epichlorohydrin (see, for example, Patent Document 1), and an example of the process (b) is known, in which an allyl compound as an olefinically unsaturated compound is reacted with hydrogen peroxide to effect epoxidization in the presence of a crystalline titanosilicate catalyst using an alcohol, a ketone or an ether as a solvent (see, for example, Patent Documents 2 and 3). In the process (a), however, 2-hydroxyisobutyric acid as a reaction substrate is a compound containing a hydroxy group and a carboxyl group in one molecule, and hence causes side reactions at the time of the desalting condensation reaction with epichlorohydrin to give a reaction yield of 70% or less which is still unsatisfactory.
Additionally, an attempt to synthesize glycidyl 2-hydroxyisobutyrate having the structure represented by the above formula (2) was made by the present inventors in accordance with the process (b), and consequently no sufficient reaction rate was attained when the known solvent, namely, alcohol, ketone or ether was used, and little target compound was obtained when no solvent was used. On the other hand, although aliphatic esters typified by ethyl acetate lead to a lower risk of production of peroxides as compared to the above-described solvents (see, for example, Non-patent Document 1), aliphatic esters are poor in compatibility with hydrogen peroxide, water and the like, and there has been no report that an aliphatic ester is used in a reaction in which an olefinically unsaturated compound is reacted with hydrogen peroxide to effect epoxidization in the presence of a crystalline titanosilicate catalyst.
Patent Document 1: Japanese Patent Application No. 2004-338680
Patent Document 2: Japanese Patent Laid-Open No. 61-183275
Patent Document 3: Japanese Patent Laid-Open No. 08-188575
Non-patent Document 1: Kanagawa Industrial Technology Research Institute (Kanagawa-Ken Sangyo-Gijutu Sogo-Kenkyu-Sho); Heisei-15 (2003) Industry-Academia-Public Cooperation Conference Proceeding (San-Gaku-Ko Koryu Happyokai Siryo), p. 97.